Abstract

The compatibility of two species of Trichoderma spp. was tested in vitro and in soil with different fertilizing elements (N, P, K, Ca) added to increase concentrations in the solid potato-based medium.
After 48 h of incubation, CaCl2, KNO3 and KH2PO4 at 400 mg/L showed an inhibitory effect on mycelial growth of Trichoderma harzianum strain (Tcomp) and Trichoderma viride strain (TV1) compared to controls varying respectively from 9.66 to 28.33 and 10.33 to 29.16 / 90.00 mm. For cons, the NH4NO3, (NH4) 2SO4 and CaSO4, 2H2O had a mean toxicity against the two strains tested, mycelial growth was ranged from 50.50 to 64.00 / 90 mm. After 7 days of incubation, both strains were able to produce conidia; their numbers have varied respectively from 6369.00 to 117833.20 / 245843.00 conidia / mm2 and 6793.00 to 67221.70 / 649635.00 conidia / mm2.
The pH was slightly basic in the potato liquid medium before culturing and after the addition of the products at different concentrations (7.64-8.60). The pH became acid after culturing of the two strains; it varied between 3.13 and 5.85. Fresh weights were low in the presence of 50 mg / L of Calcium Chloride and medium for other products from 0.01 to 2.79 and 3.04 to 6.69 respectively compared to control 7.31 - 9.28 mg. Dry weights were low in the presence of the tested products compared to controls from 7.31 - 9.28 mg.
In soil, both strains were able to grow on barley straw fragments at a concentration of 400 mg/L. The colonization percentage varied respectively between 63% and 94%.
Two strains of Trichoderma showed substantial compatibility with the most part of fertilizers tested in vitro and a great capacity to keep the soil in the presence of different elements. Thus, the antipollution properties of Trichoderma spp. can be used in agriculture in soils with excess of nitrogen and phosphate. They also have the ability to increase the capacity of nutrient uptake by plants.